Introduction: The purpose of this work is to describe the capacity for automated eye tracking performed while watching a short film clip to detect blast brain injury due to a natural gas explosion.
Methods: Design: Prospective observational study.
Setting: University-affiliated level one trauma center.
Participants: Approximately 70 civilian children and adults were accidently exposed to a natural gas explosion at a school. 36 subjects, including 4 of the hospitalized agreed to participate in this research. These blast subjects were compared to an age and gender matched cohort selected from among 561 controls recruited at a state fair.
Exposure: The study test group was exposed to a natural gas blast explosion.
Primary outcome measure: automated eye tracking metrics.
Results: Thirty-six blast exposed subjects [age (mean±sd)=35.6±17.5, 23 females] were compared using Wilcoxon signed-rank test to thirty-six age and gender matched controls. Five eye tracking metrics were significantly different between all blast survivors and age and gender matched controls selected from among the community controls. In order to create a Blast Impact Score (BIS), the subjects inside the building [N=22; 17 females] were compared to controls with no prior history of TBI [N=306; 120 females]. BIS provided an AUC of 0.835, sensitivity of 86.4% and specificity of 77.4% to discriminate between blast patients and controls. BIS also correlated with distance from the epicenter of the blast (spearman correlation=0.73; p<0.001).
Conclusions: Our data supports the use of automated eye tracking for assessment of blast brain injury. This finding is particularly relevant to military personnel who may be exposed to blast, which was previously dubbed “an invisible injury.” The ability to detect blast brain injury using an automated non-invasive technique will enable early identification of afflicted subjects and protection from repeated exposure as well as development of therapeutics.
Patient Care: Blast brain injury has been dubbed “the invisible injury” because it often does not cause immediately detectable radiographic injury, and serum or cerebrospinal fluid biomarker changes are transient. Development of a diagnostic for blast brain injury would enable identification of injured subjects for prevention of repeat injury as well as development of therapeutics.
Learning Objectives: Can an automated eye tracking algorithm performed while viewing a short film clip detect blast brain injury?
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